As a water- and oil-repelling agent composition to be used for dry cleaning of clothes and for water-proof spray, there has been heitherto used a solution-polymerization type water- and oil-repelling agent composition using a trichlorotrifluoroethane (CFC113) and/or 1,1,1-trichloroethane as a polymerization solvent from the viewpoint of water- and oil-repelling effect and easiness in handling thereof (JP-B-64635/1992 and JP-B-65113/1992).
However, it was recently decided in a worldwide scale to prohibit the production of such solvents as trichlorotrifluoroethane and 1,1,1-trichloroethane for the purpose of protection of the ozone layer, and it is urgently needed to find out a solvent replacing these toxic ones for the water- and oil-repelling agent composition.
As alternative solvents, hydrocarbons, perchloroethane, esters, ketones and the like have being studied (JP-A-78425/1993), and in these solvents a perfluoroalkyl group-containing monomer and a monomer free of fluorine atom are copolymerized. However, usually if a mixing ratio of the monomer having a perfluloroalkyl group is increased, though water- and oil-repelling property is enhanced, there is a tendency that precipitate is formed and storage stability becomes worse. If a mixing ratio of the monomer free of fluorine atom is increased, though stability is improved, the water- and oil-repelling property tends to be worse, and it is difficult to obtain a practical composition.
The present invention was made in consideration of the above-mentioned problems, and it is an object to provide a water- and oil-repelling agent composition which is excellent in storage stability and water- and oil-repelling property, and serves to remarkably decrease or completely avoid the destruction of the ozone layer, and a process for preparation thereof.